The present invention relates to a filter assembly machine. In particular, the present invention relates to a filter assembly machine comprising a feed roller having a number of peripheral seats, each designed to receive a group consisting of two cigarette lengths separated by a double filter, and on which each said double filter is joined to the respective said cigarette lengths by means of a strip fed onto the said double filter and subsequently wrapped about the said double filter and about one end of the said cigarette lengths by rolling the respective said group about its own axis in a rolling station.
The production of increasingly high-output cigarette manufacturing machines has led to the production of increasingly fast-operating filter assembly machines, for the purpose of enabling the formation of cigarette manufacturing lines on which the output of each manufacturing machine is connected to the input of a respective filter assembly machine. Continual improvement of known filter assembly machines of the aforementioned type has enabled the attainment of extremely fast operating speeds; which speeds, however, must be considered critical in that, by mere mechanical improvement alone, they allow for no future increase in production speed, without subjecting the double cigarettes being manufactured to unacceptable strain, especially at the rolling stage. During rolling, in fact, the double cigarettes being manufactured are rolled between two facing surfaces at such a speed that, if increased over and above a given value, it would inevitably result in tobacco escaping from the open ends of the respective cigarette lengths.